Rasterization converts a projected, viewport-scaled primitive
into a series of fragments.
Each fragment comprises a location of a pixel in the framebuffer along
with color, texture coordinates, and depth ().
When a line segment or polygon is rasterized,
these associated data are interpolated across the primitive to obtain
a value for each fragment.
The rasterization of each kind of primitive is controlled by a corresponding group of parameters. One width affects point rasterization and another affects line segment rasterization. Additionally, a stipple sequence may be specified for line segments, and a stipple pattern may be speicifed for polygons.
Antialiasing may be enabled or disabled individually for each primitive type. When enabled, a coverage value is computed for each fragment describing the portion of that fragment that is covered by the projected primitive. This coverage value is used after texturing has been completed to modify the fragment's alpha value (in RGBA mode) or color index value (in color index mode).